Wasted food

We have a chicken feeder that looks something like the photo below. We have it sitting on some bricks in the coop. We feed layer pellets and I'm seeing a ton of wasted food laying on the floor of the coop mixed in with the wood chips. I stopped feeding the chickens hoping if they got hungry enough they would clean up the food on the floor. I through some scratch on the floor to get them eating off the floor, etc. I did see them pick up a few bites of the pellets but for the most part they didn't eat much of it. After a couple of days I broke down and gave them food in the feeder. Anyone have any suggestions on how to stop the waste of food?

I have the same feeder and when I had this problem with my first chickens I raised the feeder so that it was hanging just enough for them to be able to eat comfortably but not low enough for them to scratch or really shovel their food. I also kept the floor underneath the feeder swept so that if anything does fall they can freely eat it without getting a mouthful of shavings and I haven't had any problems since. I had to raise their water feeder as well because when it was at their feet they would just get it all yucky, but now that it's at their face level they can no longer play in it. Maybe this will work?